1. Field of the Invention
The present invention relates to medical devices used for closure or ligation (e.g., mechanical ligation) of vessels, such as arteries or veins, such as vessels in the GI tract, for example veins in the esophagus or arteries in the GI tract, more narrowly the hemorrhoidal arteries, More particularly, the present invention relates to methods and apparatus to treat hemorrhoids without subjecting patients to pain, or with minimal pain.
2. Description of the Related Art
Hemorrhoids are a network of vascular cushions that exist as a normal part of human anatomy present in all healthy individuals. However, the term ‘hemorrhoids’ is generally used to refer to the disease process whereby a person develops symptoms when the hemorrhoids become inflamed, thrombosed, or prolapsed. When a person strains during defecation the pressure within the rectum increases and causes engorgement of the hemorrhoids. The mechanism of action is believed to be due to decreased venous return and continued arterial supply. Additionally aging causes laxity of connective tissues supporting the hemorrhoids and, hence, increases their ability to prolapse.
Hemorrhoids are simply enlarged vascular structures in the anal canal that produce discomfort, soiling of undergarments, intense itching, and in some patients, excruciating pain.
Hemorrhoids are one of the most common medical afflictions of older adults. The prevalence of hemorrhoids in the United States is approximately 13 million with a yearly incidence of 1.5 million. With a peak prevalence in the 45-65 age range, hemorrhoids particularly impact the quality of life for millions of Baby Boomers. However, only about a third of these patients seek medical treatment. This may be due to the fact that people are uncomfortable talking about this problem, that there is perception that there is no good treatment for this problem, or that there is a complicated referral pathway. The grading system used by physicians has 4 grades of increasing severity. Grade I are internal hemorrhoids that bleed. Grade II hemorrhoids are those that bleed and prolapse with straining but return by themselves. Grade III hemorrhoids bleed and prolapse with straining and require manual replacement. Grade IV hemorrhoids do not return to the anal canal and are chronically prolapsed.
Grade I hemorrhoids are treated conservatively with dietary changes (including increasing fiber and water intake) to soften the stool and medications to increase the lubrication of the stool. Grade II hemorrhoids that do not resolve with the above therapies are treated by a variety of methods, with rubber band ligation being the most common and effective. This method is fast and relatively pain-free, but has a recurrence rate of about 70% after 3 years and it usually requires several return visits to the physician. Grade III hemorrhoids are candidates for several different treatments as well, with an emphasis currently on stapled hemorrhoidopexy, doppler-guided hemorrhoidal artery ligation (DHAL), and hemorrhoidectomy. The efficacies of these therapies are approximately 80% for stapled hemorrhoidopexy and 70% for DHAL. DHAL is associated with significantly less pain that stapled hemorrhoidopexy or hemorrhoidectomy, but it is a relatively new technology and is currently not widely adopted. Grade IV hemorrhoids are typically treated by a surgical hemorrhoidectomy, which has an efficacy of 95% and almost no recurrence, but it causes a significant amount of post-operative pain and can risk complications such as permanent fecal incontinence. Patients miss an average of 11 days of work due to the severity and duration of pain.
Currently there is no treatment that is both highly effective and has a low rate of post-procedural pain and complications. Procedures with low invasiveness, such as rubber-band ligation, are used on mild hemorrhoids with few complications, but have poor long-term efficacy. More invasive procedures, such as hemorrhoidectomy and stapled hemorrhoidopexy, have good long-term efficacy, but are associated with significant pain and high complication rates. Thus, there is a need for a more effective way to treat Grade II, III, and IV hemorrhoids that is effective, but produces little pain and few complications, and has a low recurrence rate.
Methods of treatment using hemorrhoidal dearterialization (HD) work by ligating the hemorrhoidal (aka rectal) arteries, more specifically the superior hemorrhoidal arteries via hand-thrown sutures, performed through an anoscope that required significant dilation of the anal canal. HD causes the blood-engorged hemorrhoids to regain their normal structure within a few weeks. Numerous studies show that HD cures greater than 90% of grade II-IV hemorrhoids, with almost no post-operative pain in 95% of patients.
There is also great need for a treatment that can be performed outside the operating room (OR) by surgeons and non-surgeons alike. Meeting this need could decrease costs and increase the number of patients who could receive treatment. First, costs should decrease because current treatments, such as hemorrhoidectomy, can only be performed in the OR, which is tremendously expensive. Second, a new treatment performed by non-surgeons would simplify the referral pathway, which could increase the number of hemorrhoids treated. Currently, patients must first see a primary care physician and/or a gastroenterologist, who then refer to a surgeon who has the requisite skills to perform current procedures. The long cycle of care causes many patients to never receive treatment, as patients are lost between referrals. If gastroenterologists had a tool to effectively treat hemorrhoids, they could treat the patients they diagnose, preventing patients from being lost in a long referral chain. Fewer appointments would also decrease costs.